The building industry of today is dominated by conventional designs and construction practices. Conventional building techniques are very time-consuming, generally requiring a substantial amount of field labor. Moreover, mobilizing fabrication resources to the field is expensive, while it is also difficult to ensure a consistent level of quality. Conventional construction is also dominated by volumetric spaces bounded by rectangular or mixed rectangular-trapezoidal shapes.
The most notable successful departures from conventional designs and construction practices have been for large-scale enclosures for assemblies or other special purposes where domes, tent structures, and inflatable structures are becoming part of the accepted vocabulary. Success for alternative designs and construction practices has been more elusive for large enclosures through the aggregation of smaller structures for uses such as housing, condominium blocks, or office buildings. "Habitat" at the 1967 Montreal Expo is the only famous non-traditional project of this genre, built of concrete in rectangular modularity, but it was notable for its high cost and has not been duplicated.
Prefabrication of building components, such as trusses and walls, is well known in the art and reduces some of the disadvantages (noted above) inherent in conventional field construction. Construction using these standardized, prefabricated components, however, continues to suffer from substantial limitations. Achieving complex or distinctive geometries using prefabricated components requires a large number of different components, which elevates their cost of supply. And, only a relatively small range of different overall structure geometries may be economically achieved using known standardized and prefabricated components. Moreover, many standardized and prefabricated components are not designed or cannot be designed to be interchangeably fastened to the gamut of other prefabricated components produced by the same manufacturer.
Using geodesic space fillers of varieties other than rectangular modularity for building construction represents a departure from conventional design. With such space fillers, smaller parts can create modules which can then be used to construct buildings of large sizes and unusual forms.
One known space filling geometry is the rhombic dodecahedron. An unmodified, closed module of this type has 12 sides, with each side consisting of a 4-edged rhombus. Being more complex for filling space than conventional square or rectangular cubic (6-sided) units, the rhombic dodecahedron represents a balance between allowing the construction of unusual forms while keeping the overall number of sides down to an economical number. The rhombic dodecahedron is characterized by having eight 3-point vertices, and six 4-point vertices.
The basic rhombic dodecahedral module may also be modified, for instance, by `stretching` selected side shapes from rhombic forms into hexagons or `twisting` selected side shapes into trapezoids. Such modified forms may have twelve 3- point vertices and two 4-point vertices. Myriad variations of these modified forms are possible, depending on the acuteness of the angles embodied in the side shapes.
Though the rhombic dodecahedral form is known as a space filling geometry (Peter Pearce, Structure in Nature is a Strategy for Design), this geometry is not presently applied to the construction of economical modular structures.